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C D Fletcher

Publications and source records attributed to C D Fletcher.

At least 271 records · Page 15Linked to original sources
PubMed1990

Intranodal myofibroblastoma presenting in the submandibular region: evidence of a broader clinical and histological spectrum.

Intranodal myofibroblastoma is an uncommon benign mesenchymal tumour of lymph nodes which was first described in May 1989. All the cases described to date have presented exclusively in the groin, a feature which has been regarded as distinctive. Two new cases are presented herein, both of which arose in the submandibular region of middle-aged females. Both lesions showed histological features marginally different from the cases originally described, which may reflect their different anatomical location. Immunohistochemical staining revealed positivity for muscle-specific actin (HHF 35), as previously described, and ultrastructural examination in one case confirmed the presence of myofibroblasts. The data presented suggest that this distinctive lesion has a broader clinicopathological spectrum than previously realised.

Adult↗
PubMed1990

Cutaneous heterotopic meningeal nodules.

The clinical, light microscopic and immunohistochemical features of six cutaneous heterotopic meningeal nodules (primary, or type I, cutaneous meningiomas) are described. These are rare lesions of the scalp and back which generally present at birth or in childhood. They appear as small subcutaneous fibrous nodules, with no specific clinical features although they can be associated with abnormalities of spinal closure. Microscopically, they show a variable architecture but have similar cytological features. Important diagnostic features include psammoma and small collagenous bodies. An intimate relationship to nerves is seen in some cases, and this may be of significance with regard to the development of these lesions. As with intracranial meningiomas, there is widespread vimentin expression, and most cases show epithelial membrane antigen expression.

Adult↗
PubMed1990

Effects of bilateral oophorectomy on lipoprotein metabolism.

The effects of surgical menopause on lipoprotein levels and their time course were studied in 31 premenopausal women who were undergoing hysterectomy and bilateral oophorectomy for non-malignant conditions. Lipoprotein levels were measured before oophorectomy and afterwards at 6 and 12 weeks, then at intervals of 3 months for 18 months. Low density lipoprotein (LDL) cholesterol levels rose significantly (P less than 0.05) in the 6 weeks after operation from a mean of 3.57 (SD 0.66) mmol/l to 4.21 (SD 0.84) mmol/l with no significant changes thereafter. There were no significant changes in cholesterol in the other density fractions or in triglyceride levels. High density lipoprotein (HDL) subfractions were measured in 10 of the women to assess any change in the relative amounts of cholesterol carried on HDL2 and HDL3, since the protective effect of HDL is believed to be conferred by the HDL2 fraction only. No significant change was found in either fraction. The increase in LDL cholesterol would be expected to result in an appreciable increase in the risk of developing coronary heart disease, but cannot wholly account for the increase in cardiovascular disease associated with oophorectomy.

Adult↗
PubMed1990

Benign fibrous histiocytoma of subcutaneous and deep soft tissue: a clinicopathologic analysis of 21 cases.

Twenty-one cases of benign fibrous histiocytoma arising in noncutaneous soft tissue are reported. These tumors presented most often in young to middle-aged adults with a predominance in males. They originated in deep subcutis (16 cases), skeletal muscle (three cases), and mesentery (two cases). The most common sites of incidence were the lower limb (eight cases) and head and neck region (six cases). Four of 12 cases with follow-up (median 3.0 years) recurred locally; all had originated in the subcutis. None metastasized. These lesions are generally larger and better circumscribed than their cutaneous counterparts. They are also usually more monomorphic and have a more consistent storiform pattern than the latter. A pericytomalike vascular pattern (six cases), xanthoma cells (six cases), and multinucleate giant cells (six cases) may be prominent. Hyaline or myxoid degeneration of the stroma is common. Rare features include small foci of necrosis and intravascular growth. Immunohistochemically, deep benign fibrous histiocytoma shows no evidence of true monocyte/macrophage differentiation and its histogenesis remains uncertain. The differential diagnosis includes malignant fibrous histiocytoma, dermatofibrosarcoma and hemangiopericytoma.

Adolescent↗
PubMed1990

Mutation of the p53 gene in human soft tissue sarcomas: association with abnormalities of the RB1 gene.

Soft tissue sarcomas have been examined for alterations in the p53 gene. In six sarcomas, loss or rearrangement of both alleles of this gene was detected while in a further seven sarcomas, point mutation or absence of transcription of the p53 gene was observed. Abnormalities of the p53 gene were found in several classes of soft tissue sarcoma, including leiomyosarcomas, rhabdomyosarcomas and malignant fibrous histiocytomas. Our studies also show that abnormalities of the RB1 suppressor gene and of the p53 gene frequently occur together. These results are consistent with the idea that the p53 gene is a tumour suppressor gene and indicate that coincident inactivation of more than one tumour suppressor gene may, in some cases, be required for tumour development.

Base Sequence↗
PubMed1989

Spindle cell and pleomorphic lipoma: an immunohistochemical study and histogenetic analysis.

Twenty-two spindle cell lipomas and seven pleomorphic lipomas were investigated immunohistochemically in order to study the differentiation of the non-adipocytic elements. In all cases, neither spindle cells nor pleomorphic cells reacted with antibodies to a monocyte/macrophage antigen (MAC-387), fibronectin, laminin or type IV collagen. The absence of demonstrable basement membrane material argues against the possible prelipoblastic nature of these cells. With the antibody to S-100 protein, spindle cells were immunonegative, whereas pleomorphic cells sometimes revealed an intracytoplasmic weak to moderate staining reaction. In the light of what is known about the development of adipose tissue, our results would support the hypothesis of Bolen and Thorning (Am J Surg Pathol 1981; 5: 435-441) that spindle cell lipoma is composed of adipocytes and non-fat storing immature mesenchymal cells. It would appear that pleomorphic lipoma is similarly derived but that in some cases adipocytic differentiation is also abnormal. The characteristic clinical distribution of these two types of tumour may be of relevance in determining the cause of these unusual benign patterns of differentiation.

Adult↗
PubMed1989

Soft tissue tumors.

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Angiolymphoid Hyperplasia with Eosinophilia↗
PubMed1989

Structural alterations of the RB1 gene in human soft tissue tumours.

Sixty-nine primary soft tissue tumours were examined for alterations of the RB1 gene which has previously been implicated in the genesis of retinoblastoma. In three tumours loss of both alleles of this gene (homozygous deletion) was detected. Two of these, both leiomyosarcomas, contained a chromosomal breakpoint within the RB1 gene, while in the third tumour, a radiation induced sarcoma, complete deletion was observed. Using a probe that detects a polymorphic locus within the RB1 gene we found loss of only one allele (heterozygous deletion) in 33% of soft tissue sarcomas examined, including two leiomyosarcomas, a malignant peripheral nerve sheath tumour, a rhabdomyosarcoma and a chondrosarcoma. When taken together our results suggest that alterations of the RB1 locus may play an important part in the pathogenesis of soft tissue tumours and particularly in leiomyosarcomas which accounted for four of the eight RB1 alterations observed in this study.

Alleles↗
PubMed1989

Solitary circumscribed neuroma of the skin (so-called palisaded, encapsulated neuroma). A clinicopathologic and immunohistochemical study.

Solitary, circumscribed neuroma is a distinctive benign cutaneous tumor that was first described under the name "palisaded, encapsulated neuroma" over 15 years ago. Despite the fact that it is not uncommon, it has received minimal attention and is very poorly known among pathologists. We have studied the clinicopathologic and immunohistochemical features of 39 cases. These lesions almost always present on the face or close to a mucocutaneous junction in middle-aged adults. Most examples measure less than or equal to 0.5 cm and are composed of a partially encapsulated mass of bland Schwann cells and innumerable tiny axons arranged in interlacing fascicles. The capsule is composed of perineural cells that show epithelial membrane antigen positivity. Solitary, circumscribed neuroma is not associated with von Recklinghausen's neurofibromatosis, nor is there evidence to support its possible relationship to the type IIb multiple endocrine neoplasia syndrome. This entity warrants wider recognition.

Adolescent↗
PubMed1989

Effects of treatment with oestradiol/levonorgestrel on bone, lipoproteins and hormone status in postmenopausal women.

The aim of the study was to investigate the effects of an oestradiol/levonorgestrel regimen, administered parenterally, on bone metabolism, bone density, lipoprotein metabolism and hormone status. Twenty-five women who had undergone a surgical menopause had an oestradiol/levonorgestrel-containing vaginal ring pessary in situ for 6 months. Within the first month there were sustained changes in the biochemical indices of bone metabolism in keeping with a marked reduction in bone turnover and decrease in bone resorption. Bone mineral content in the distal forearm was measured in 14 patients and a small increase was noted in every patient. Levonorgestrel was well absorbed and the serum levels remained almost constant throughout treatment. There was a gradual increase in serum total oestradiol which became significant at 6 months. Dialysable oestradiol levels rose from 2.6% of total oestradiol at 0 time to 3.3% at 1 month with no further change thereafter. SHBG levels were 23% of pretreatment levels at 6 months. There were sustained decreases in triglyceride, VLDL and HDL cholesterol levels and a transient fall in LDL cholesterol. Total HDL, HDL2 and HDL3 cholesterol levels were reduced by 25, 40 and 21% respectively. The results suggest that levonorgestrel exerts a protective influence on bone either directly or by its effect on the proportion of oestradiol circulating in the free, physiologically active form. The effects on lipoproteins were predominately those of the progestogen component, the lipoprotein risk factors for coronary heart disease being adversely affected.

Administration, Intravaginal↗
PubMed1989

Epithelial membrane antigen expression by the perineurial cell: further studies of peripheral nerve lesions.

We have previously shown that a range of anti-epithelial membrane antigen monoclonal antibodies show immunoreactivity with the perineurial fibroblast, both in normal nerves and within a range of common peripheral nerve tumours. We have extended these observations by studying a further collection of peripheral nerve lesions, including some which have previously been thought to have an origin from the perineurial cell. The results provide further evidence that these antibodies reliably stain perineurial cells and that in conjunction with antisera to S-100 protein and neurofilaments, the relative contributions of the perineurial fibroblast, Schwann cell and neurone can be assessed within a nerve-related tumour/lesion. The perineurial fibroblast is an important component of some peripheral nerve lesions.

Fibroblasts↗
PubMed1989

Digital pacinian neuroma: a distinctive hyperplastic lesion.

Neural tumours composed solely of Pacinian corpuscles or showing focal Pacinian differentiation are extremely rare and have only occasionally been reported in the literature. All such lesions to date have been benign. Three lesions are described herein which presented as painful digital masses in middle-aged adults and which were composed of abnormal aggregates of morphologically mature Pacinian corpuscles and intervening small nerves. Only five similar cases have been previously recorded. Possible pathogenetic mechanisms of this unusual hyperplastic phenomenon are discussed.

Adult↗
PubMed1989

Lipoprotein and apolipoprotein levels in postmenopausal women on continuous oestrogen/progestogen therapy.

Levels of serum lipoproteins and apolipoproteins were monitored for 48 weeks in two groups of women taking part in a double-blind trial of continuous oestrogen/progestogen with and without oestriol. There were no differences between the effects of the two treatments on the substances measured. Triglycerides did not change and there was a transient fall in very low density lipoprotein cholesterol. Low density lipoprotein cholesterol fell over the first 24 weeks but rose thereafter to pretreatment levels. There was a decrease in high density lipoprotein (HDL) cholesterol due to a transient fall in HDL2 cholesterol and a gradual decrease in HDL3 cholesterol. Consequently, the only change in lipid levels present after 48 weeks was a decrease in HDL3 cholesterol, the clinical significance of which is uncertain. There was, however, an increase in apoprotein B levels and decreases in apoprotein AI and AII levels. These alterations in apoprotein levels may be unfavourable, since apoprotein B levels have been positively correlated and apoprotein AI and AII levels negatively correlated with coronary heart disease.

Apolipoproteins↗
PubMed1988

Changes in the bone and liver isoenzymes of alkaline phosphatase in postmenopausal women being treated with norethisterone.

The effects of norethisterone therapy on alkaline phosphatase isoenzyme activities were studied in a group of postmenopausal women. There was a significant fall in total alkaline phosphatase activity after 8 wk which was still in evidence after 24 wk. Both bone and liver alkaline phosphatase isoenzyme activities were decreased during the first 16 wk on treatment, but after 24 wk only the bone phosphatase activity was significantly lower than the pretreatment level. The other biochemical indices of bone metabolism and liver function were also measured during the study. The results indicate that bone specific alkaline phosphatase activity is a more sensitive index of bone activity than total alkaline phosphatase and that monitoring of total activity may in some instances be misleading.

Alkaline Phosphatase↗